From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 33B44243399 for ; Sat, 23 Aug 2025 13:43:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755956630; cv=none; b=CiJG3HBhcj+E5YXE9X23FybL9J+9fAcOp/Oq5mNw8tshkH6eokGNsf7OMrSAJloFxrWOVi4UOUuog4x1ATyogPJ+vf7oRufQi9Z0jbTG/Eng5rEI9Hdxibsi8my0WfASKVDOkojQDR6SzsJgYPNv7ws6104BEoMPezxplqXV/XQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755956630; c=relaxed/simple; bh=QPyL9FaJuuPyrsICzcrcMdqXlnoJgXA2Z3uwvHiCB28=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=d52qkZTwrqVEN4+GD+LTeTzQDtkN0QUmn2ON4agCig0E4tCjPRctBlF0EMVrVKXtqCxtHHUjYEIl/P+8zx0siVtNJ28u9Z+GldINmrfuWJQo1tNO7knIiTwx8TGFkYSN+nAk6ZZ7KZk+jJRfU0oL6PFh5dC14ZDEa/sjg9q4D00= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fAoAR1Ne; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fAoAR1Ne" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CB63C4CEF4; Sat, 23 Aug 2025 13:43:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755956629; bh=QPyL9FaJuuPyrsICzcrcMdqXlnoJgXA2Z3uwvHiCB28=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fAoAR1NepNU+qv/+TLkiO0iXkfHqeJYasZ04+piobhjzXssfuRvjKTHGrI5HwaJCk 8v+xiuzFM50e2zprw/H/AS8IyE5CyyW2wiAFjVBBvwm9NzNjlJiXmlIWXR/UZANU6Z 4rkeK1pbl7jcOy4zgQygBUyL6pzyjyL7dSaslxsRafQB/7hBCP83ZnqRFKHWHWopCa JqdD3On43sccCQKVrpB9WicZl/uj6aUP+eV/bC/8dAt0TQcFJfEUUvs7qX2QSE9y0r aiY6N5g9bthtgptX62gUQsFFZUH2WExQH0E1NVJNr1WgUu5jeinna3hWCgLZIamMIk lB2WcRFkIHfMw== From: Sasha Levin To: stable@vger.kernel.org Cc: Robin Murphy , Eric Auger , Joerg Roedel , Sasha Levin Subject: [PATCH 6.16.y 2/2] iommu/virtio: Make instance lookup robust Date: Sat, 23 Aug 2025 09:43:46 -0400 Message-ID: <20250823134346.2145572-2-sashal@kernel.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250823134346.2145572-1-sashal@kernel.org> References: <2025082258-exert-mousy-2b51@gregkh> <20250823134346.2145572-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Robin Murphy [ Upstream commit 72b6f7cd89cea8251979b65528d302f9c0ed37bf ] Much like arm-smmu in commit 7d835134d4e1 ("iommu/arm-smmu: Make instance lookup robust"), virtio-iommu appears to have the same issue where iommu_device_register() makes the IOMMU instance visible to other API callers (including itself) straight away, but internally the instance isn't ready to recognise itself for viommu_probe_device() to work correctly until after viommu_probe() has returned. This matters a lot more now that bus_iommu_probe() has the DT/VIOT knowledge to probe client devices the way that was always intended. Tweak the lookup and initialisation in much the same way as for arm-smmu, to ensure that what we register is functional and ready to go. Cc: stable@vger.kernel.org Fixes: bcb81ac6ae3c ("iommu: Get DT/ACPI parsing into the proper probe path") Signed-off-by: Robin Murphy Tested-by: Eric Auger Link: https://lore.kernel.org/r/308911aaa1f5be32a3a709996c7bd6cf71d30f33.1755190036.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/virtio-iommu.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 532db1de201b..b39d6f134ab2 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -998,8 +998,7 @@ static void viommu_get_resv_regions(struct device *dev, struct list_head *head) iommu_dma_get_resv_regions(dev, head); } -static const struct iommu_ops viommu_ops; -static struct virtio_driver virtio_iommu_drv; +static const struct bus_type *virtio_bus_type; static int viommu_match_node(struct device *dev, const void *data) { @@ -1008,8 +1007,9 @@ static int viommu_match_node(struct device *dev, const void *data) static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode) { - struct device *dev = driver_find_device(&virtio_iommu_drv.driver, NULL, - fwnode, viommu_match_node); + struct device *dev = bus_find_device(virtio_bus_type, NULL, fwnode, + viommu_match_node); + put_device(dev); return dev ? dev_to_virtio(dev)->priv : NULL; @@ -1160,6 +1160,9 @@ static int viommu_probe(struct virtio_device *vdev) if (!viommu) return -ENOMEM; + /* Borrow this for easy lookups later */ + virtio_bus_type = dev->bus; + spin_lock_init(&viommu->request_lock); ida_init(&viommu->domain_ids); viommu->dev = dev; @@ -1229,10 +1232,10 @@ static int viommu_probe(struct virtio_device *vdev) if (ret) goto err_free_vqs; - iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev); - vdev->priv = viommu; + iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev); + dev_info(dev, "input address: %u bits\n", order_base_2(viommu->geometry.aperture_end)); dev_info(dev, "page mask: %#llx\n", viommu->pgsize_bitmap); -- 2.50.1